This invention relates to an apparatus for intubation of lacrimal duct (lacrimal drainage pathway) for treatment of lacrimal duct obstruction and so on.
A typical prior method of silicone intubation is shown in Japanese Patent Publication No. 56-50579.
In the prior method, the silicone tube is drawn into the lacrimal duct by a probe which is pulled out from the inferior nasal meatus.
Therefore, in the previous methods, a probe as a guide must be pulled out from the nostril. This maneuver is difficult. It is not rare that it takes a lot of time to retrieve the probes from the nostril or the retrieval is impossible.
For many years the present inventor has studied keenly for the treatment of lacrimal duct obstruction and dry eye, apparatus for intubation of the lacrimal duct which can be used easily with decreased pain to patients, can be quickly and correctly inserted into the lacrimal duct, is not easily dislocated during the intubation period, and can be easily removed after accomplishment of treatment.
As a result, various kinds of apparatus for intubation have been invented, for example, as shown in Japanese Patent Publication No. 2811283, Japanese Patent Publication No. 2572340, Japanese Patent Publication No. 2539325, Japanese Patent Publication No. 8-19271, Japanese Patent Publication No. 8-30104, Japanese Patent Publication No. 9-276318, Japanese Patent Publication No. 2572352, Japanese Patent Publication No. 10-256109.
Above all, the apparatus shown in Japanese Patent Publication No. 2539325 is a typical invention made by the present inventor.
As shown in FIGS. 1xcx9c3, in the typical prior art apparatus, the central part 20xcx9c40 mm of the tube 50xcx9c120 mm in length is thinner and softer, and the bilateral parts of the tube are thicker, and both ends are sharp pointed and closed. Thus, the apparatus for intubation of the lacrimal duct resembling a xe2x80x9cnunchakuxe2x80x9d type device which is used by Chinese martial art practitioners, has been developed.
FIG. 3 (A) shows a cross sectional view showing a conventional nunchaku-style tubing.
As shown in FIG. 3, the thicker tube 42 is pushed into the lacrimal duct with the probe 61 which is inserted into the thicker tube. At the time, if there is too much lubricity between the probe 61 and the thicker tube 42, the tube sometimes cannot be inserted into the lacrimal duct because the tip of the probe 61 slips on the inner surface X of the thicker tube, whereas, if the lubricity between the probe 61 and the thicker tube 42 is poor, the thicker tube sometimes turns back in the lacrimal duct together with the probe 61 when the probe 61 is removed from the thicker tube 42 (see for example, Kurihashi K: Dacryology, Medical A01 Shuppan, Inc, 1998, p.171).
One object of the present invention is to provide an apparatus which can be easily pushed into the lacrimal duct with the tip of a probe by making the inner surface of the thicker tube uneven.
Another object of the present invention is to provide an apparatus in which the probe can be easily removed from the thicker tube by making better lubricity between the probe and the thicker tube.
According to one mode of the invention, a step(s), protuberance(s), groove(s), other irregular surface and/or septum (septa) is applied to the inner surface of the thicker tube to make the inner surface uneven, and a septum (septa) is also applied.
By doing so, the thicker tube can be easily pushed into the lacrimal duct because the tip of the probe touches the step(s), protuberance(s), groove(s), other irregular surface or septum (septa). Furthermore lubricants such as olive oil, lipiodol ultrafluid and/or ointment are applied to the inner part of the thicker tube and/or probe. By doing so, better lubricity is provided between the thicker tube and the surface of the probe.
Although the columnar shape is good for the shape of the inner surface of the thicker tube, the frustum of the circular cone is better for the shape of the inner surface to operate the apparatus for intubation of the lacrimal duct. The shape of the frustum of the circular cone makes the thicker tube able to be pushed more effectively into the lacrimal duct.
The materials and shapes for the thicker tube and probe described in Japanese Patent Publication No. 2811283, Japanese Patent Publication No. 2572340,Japanese Patent Publication No. 2539325, Japanese Patent Publication No. 2572352, Japanese Patent Publication No. 8-19271, Japanese Patent Publication No. 8-30104, Japanese Patent Publication No. 9-276318, Japanese Patent Publication No. 10-256109 can be used for the present invention.